The White House may hope that Comey's Republican background and strong credentials will help him through Senate confirmation at a time when some of Obama's nominees have been facing tough battles. Republicans have said they see no major obstacles to his confirmation, although he is certain to face tough questions about his hedge fund work, his ties to Wall Street as well as how he would handle current, high-profile FBI investigations.
The FBI is responsible for both intelligence and law enforcement with more than 36,000 employees. It has faced questions in recent weeks over media leak probes involving The Associated Press and Fox News; the Boston Marathon bombings; the attack at Benghazi, Libya, that killed four Americans; and two vast government surveillance programs into phone records and online communications.
The leaker of those National Security Agency programs, former NSA contractor Edward Snowden, also is the subject of an ongoing criminal investigation. And just this week Mueller revealed the FBI uses drones for surveillance of stationary subjects and said the privacy implications of such operations are worthy of debate.
Comey played a central role in holding up Bush's warrantless wiretapping program, one of the administration's great controversies and an episode that focused attention on the administration's controversial tactics in the war on terror.
In dramatic testimony to the Senate Judiciary Committee in 2007, Comey said he thought the no-warrant wiretapping program was so questionable that he refused to reauthorize it while serving as acting attorney general during Ashcroft's hospitalization. Comey said when he learned that the White House chief of staff and counsel were heading to Ashcroft's room despite his wife's instructions that there be no visitors, Comey beat them there and watched as Ashcroft turned them away.